Safety and Validation Engineer; REMOTE

Hukari Ascendent is a Women-Owned, Small Business specializing in comprehensive engineering and technical support services associated with commercial nuclear power and other Department of Energy (DOE) nuclear activities.

Job Title: Safety Methods and Validation Engineer

Duration: Contract (12 months)

Location: Bellevue, WA (Remote)

Summary:

Hukari Ascendent is seeking a Safety Methods and Validation Engineer to support validation activities for an advanced reactor’s plant-scale thermal-hydraulic analysis tools. Reporting to the Manager, Plant Thermal Hydraulics Validation, the engineer will support verification, validation, uncertainty quantification, and comprehensive code assessment. The position requires expertise in system-level thermal-hydraulics, thermal-fluids behavior, fluid-structure interaction, and benchmarking computational models against high-quality experimental data.

Responsibilities include:

• Support verification, validation, and uncertainty quantification (VVUQ) activities for plant-scale thermal-hydraulic analysis tools.
• Perform system-level steady-state and transient thermal-hydraulic simulations to evaluate model behavior, accuracy, and limitations.
• Develop and execute code assessment plans, including validation matrices, test selection, and quantitative comparison methodologies.
• Interpret and apply experimental data from separate effects and integral test facilities to support model validation and closure of technical gaps.
• Define validation needs, develop test requirements, and collaborate with test engineering teams to align model gaps with experimental programs.
• Document V&V methodologies, model assumptions, validation results, and uncertainty analyses for internal design processes and regulatory submittals.
• Collaborate with multidisciplinary teams to support plant design, safety analysis, and licensing workflows.
• Apply and improve SQA and NQA-1 modeling quality practices, ensuring traceability and configuration control of analysis inputs, models, and results.

Required Qualifications:

• Degree in Mechanical, Nuclear, or Chemical Engineering, or a related field.
• 3+ years of experience in system-level thermal-hydraulic analysis and code assessment for nuclear or complex energy systems.
• Experience in code assessment, including model-to-test comparison, validation metric development, and uncertainty quantification.
• Hands-on experience with experimental thermal-hydraulic data, including data analysis, uncertainty evaluation, and comparison against system-level predictions.
• Proficiency with system analysis tools (e.g., RELAP5-3D, GOTHIC, or equivalent) applied to plant-scale transient and steady-state evaluations.
• Strong foundation in thermal-hydraulic and reactor system behavior relevant to advanced reactor designs.
• Experience developing validation strategies, defining data needs, and coordinating with experimental programs.
• Strong analytical thinking, clear technical communication, and the ability to manage multiple validation tasks in parallel.

Preferred Qualifications:

• Experience with SQA and NQA-1 quality assurance practices for modeling workflows.

Hukari Ascendent offers an excellent benefits package including medical, dental, vision, and life insurance, 401(k) plan, and paid time off.

Opportunities with Hukari Ascendent change frequently. For a complete listing of our current openings, please visit our website at

Hukari Ascendent is an Equal Opportunity/Affirmative Action Employer. All qualified applicants receive consideration for employment without regard to age, disability, race, color, religion, creed, national origin, sex, marital status, sexual orientation, veteran or military status including disabled veterans and Vietnam era veterans, or other protected status.

Hukari Ascendent maintains a drug-free workplace.